Switched to a different coolant on my Haas VF-2 last month and the surface finish changed completely

I went from a generic water-soluble cutting fluid to a semi-synthetic coolant after reading about tramp oil buildup, and within a week my aluminum parts stopped having that dull, streaky look and started coming out with a mirror-like shine, has anyone else noticed a huge difference just from swapping coolant?

3 comments

3 Comments

mark_thomas17d ago

Read an article from some coolant manufacturer (MSC probably) that said the surfactant package in semi-synthetics keeps chips from welding to the tool, which is what causes that streaky finish in aluminum. Sounds like that's exactly what happened to you. Just be careful when you switch over because mixing leftover water-soluble stuff with semi-synthetic can make a nasty sludge, I learned that one the hard way after a messy cleanup on my old machine.

ben_nguyen18d ago

A semisynthetic turned my parts from dull to shiny in one week too.

bettys5118d ago

Yeah that sounds about right. Semi-synthetic coolants do a much better job flushing away fines and keeping the cutting zone clean, which makes a huge difference on aluminum especially. Make sure you check your concentration with a refractometer, though, too rich and it gets gummy, too lean and you lose that shiny finish you just got. Also, keep an eye on your coolant pH as it ages, because that can cause staining too if it drops too low. A good sump maintenance schedule with regular skimming will keep that mirror-like look longer.